Today Mr A found an old calculator of mine and we introduced him to doing simple addition with it. He would happily type in "2 + 2" and then count on my fingers to work out the answer was 4, then stare in wonder as the calculator "got it right" over and over again.
Not only did this simple game show us that Mr A was more fluent with numbers than we thought but he was learning a lot about simple maths. He even recognized that you could tip win different numbers but end up with the same answer like 4 + 3 and 5 + 2. I think it may be time for me to make up a wee maths kit for Mr A with 10 each of 10 different objects so he can explore and extend these concepts as I think a lot of the next few days will be spent with calculator in hand.